noaa-recon-17175 Torneträsk 1500 Year Tree Ring MXD and TRW Temperature Reconstructions Melvin, T.M.; Grudd, H.; Briffa, K.R. Torneträsk 1500 Year Tree Ring MXD and TRW Temperature Reconstructions 2014-09-11 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/17175 Investigator T.M. Melvin Investigator H. Grudd Investigator K.R. Briffa earth science paleoclimate climate reconstructions|tree ring age,null,null,year Common Era,null,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring surface temperature,ring density,null,degree Celsius,May-Aug,climate reconstructions|tree ring,filtered,null,N,based on latewood density; 10yr low pass filter earth science paleoclimate climate reconstructions|tree ring number of samples,null,null,count,null,climate reconstructions|tree ring,null,null,N,number of tree ring samples earth science paleoclimate climate reconstructions|tree ring surface temperature,ring density,two standard error,degree Celsius,May-Aug,climate reconstructions|tree ring,null,null,N,based on latewood density; calculated when sample count >4 trees earth science paleoclimate climate reconstructions|tree ring surface temperature,ring width,null,degree Celsius,May-Aug,climate reconstructions|tree ring,null,null,N,null earth science paleoclimate climate reconstructions|tree ring surface temperature,ring width,two standard error,degree Celsius,May-Aug,climate reconstructions|tree ring,null,null,N,calculated when sample count >4 trees earth science paleoclimate climate reconstructions|tree ring surface temperature,ring width,null,degree Celsius,May-Aug,climate reconstructions|tree ring,filtered,null,N,10yr low pass filter earth science paleoclimate climate reconstructions|tree ring surface temperature,ring density,null,degree Celsius,May-Aug,climate reconstructions|tree ring,null,null,N,based on latewood density earth science paleoclimate reconstructions air temperature geoscientificInformation Air Temperature Reconstruction -39 AD 2010 AD 1989 cal yr BP -60 cal yr BP Complete 68.21 68.31 19.45 19.8 400 400 Continent Europe Northern Europe Scandanavia Sweden Torneträsk>LATITUDE 68.25>LONGITUDE 19.6 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Thomas M. Melvin, Håkan Grudd, Keith R. Briffa 2013 The Holocene 23 3 364-373 10.1177/0959683612460791

We describe the analysis of existing and new maximum-latewood-density (MXD) and tree-ring width (TRW) data from the Torneträsk region of northern Sweden and the construction of 1500 year chronologies. Some previous work found that MXD and TRW chronologies from Torneträsk were inconsistent over the most recent 200 years, even though they both reflect predominantly summer temperature influences on tree growth. We show that this was partly a result of systematic bias in MXD data measurements and partly a result of inhomogeneous sample selection from living trees (modern sample bias). We use refinements of the simple Regional Curve Standardisation (RCS) method of chronology construction to identify and mitigate these biases. The new MXD and TRW chronologies now present a largely consistent picture of long-timescale changes in past summer temperature in this region over their full length, indicating similar levels of summer warmth in the medieval period (MWP, c. ce 900-1100) and the latter half of the 20th century. Future work involving the updating of MXD chronologies using differently sourced measurements may require similar analysis and appropriate adjustment to that described here to make the data suitable for the production of un-biased RCS chronologies. The use of 'growth-rate' based multiple RCS curves is recommended to identify and mitigate the problem of 'modern sample bias'. STUDY NOTES: Summer (May to August) temperature reconstructions for Torneträsk in northern Sweden derived using firstly MXD measurements from 130 pine trees (Pinus sylvestris-Scots Pine) for AD 441 to 2010 and secondly TRW measurements from 650 pine trees for AD -39 to 2010. MXD data are derived from dry dead wood and living trees while the TRW data was also derived from subfossil lake material. The 10-year low pass chronologies are similar but the TRW has smaller error margins. For further information see Melvin et al. (2012) paper. Metadata, supplementary data, computer programs and code are all online at: http://www.cru.uea.ac.uk/cru/papers/melvin2012holocene/

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/europe/sweden/tornetrask2013temp-mxd.txt Data File; Torneträsk MXD Temperature Reconstruction GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/europe/sweden/tornetrask2013temp-trw.txt Data File; Torneträsk TRW Temperature Reconstruction USA/NOAA DIF Version 9.8.4 2019-04-11 2019-04-11